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<a name="IA_002d64-Function-Attributes"></a>
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Next: <a href="M32C-Function-Attributes.html#M32C-Function-Attributes" accesskey="n" rel="next">M32C Function Attributes</a>, Previous: <a href="H8_002f300-Function-Attributes.html#H8_002f300-Function-Attributes" accesskey="p" rel="prev">H8/300 Function Attributes</a>, Up: <a href="Function-Attributes.html#Function-Attributes" accesskey="u" rel="up">Function Attributes</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p>
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<a name="IA_002d64-Function-Attributes-1"></a>
<h4 class="subsection">6.33.12 IA-64 Function Attributes</h4>

<p>These function attributes are supported on IA-64 targets:
</p>
<dl compact="compact">
<dd><a name="index-syscall_005flinkage-function-attribute_002c-IA_002d64"></a>
</dd>
<dt><code>syscall_linkage</code></dt>
<dd><p>This attribute is used to modify the IA-64 calling convention by marking
all input registers as live at all function exits.  This makes it possible
to restart a system call after an interrupt without having to save/restore
the input registers.  This also prevents kernel data from leaking into
application code.
</p>
<a name="index-version_005fid-function-attribute_002c-IA_002d64"></a>
</dd>
<dt><code>version_id</code></dt>
<dd><p>This IA-64 HP-UX attribute, attached to a global variable or function, renames a
symbol to contain a version string, thus allowing for function level
versioning.  HP-UX system header files may use function level versioning
for some system calls.
</p>
<div class="smallexample">
<pre class="smallexample">extern int foo () __attribute__((version_id (&quot;20040821&quot;)));
</pre></div>

<p>Calls to <code>foo</code> are mapped to calls to <code>foo{20040821}</code>.
</p></dd>
</dl>




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